A Hall effect probe to measure magnetic field strengths needs to be calibrated in a known magnetic field. Magnetic fields can be very precisely measured by measuring the cyclotron frequency of protons. A testing laboratory adjusts the magnetic field until the proton's cyclotron frequency is 10.0 MHz. At this field strength, the Hall voltage on the probe is 0.543 mV when the current through the probe is 0.15 mA. Later, when an unknown magnetic field is measured, the Hall voltage for the same current is 1.735 mV. What is the strength of the latter magnetic field.